Q.Two major environmental issues facing the world today are ____________ and _____________.
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🔒 Start your 14-day free trial to unlock the full solution →Concept understanding — Environmental Degradation
Environmental Degradation: When Nature's Balance Breaks
Think of a pond. You throw a stone in — the ripples spread, then settle. The pond absorbs it. Now imagine you dump a bucket of paint into that same pond every day. The water turns murky, the fish die, the plants rot. The pond can no longer clean itself. That is degradation — the loss of nature's ability to sustain itself and us.
The Intuition First
Every morning you breathe air, drink water, eat food grown in soil. These are not "products" made in factories — they are gifts from the environment. But when we take too much (overfish the ocean) or dump too much (chemicals into a river), we damage the very systems that provide these gifts. The environment stops functioning properly. That damage is environmental degradation.
The Precise Meaning
In economics, environmental degradation refers to the decline in the quality and productive capacity of natural resources — air, water, soil, forests, biodiversity — caused by human activity. It is not a natural event like a volcanic eruption; it is the result of how we produce, consume, and dispose.
Environmental degradation is not the same as resource depletion. Depletion means we use up a resource (like oil). Degradation means we damage the resource's quality even if it still exists physically — polluted water is still water, but you cannot drink it.
Why It Matters in Economics
Here is the core economic problem: the environment provides four essential functions that have no market price.
- Source function — it supplies raw materials (wood, minerals, water)
- Sink function — it absorbs and recycles our waste (CO₂, sewage)
- Life-support function — it regulates climate, purifies air, maintains biodiversity
- Amenity function — it gives us recreation, beauty, spiritual value
When we degrade the environment, we damage all four. But because these functions are free (no one charges you for the oxygen a tree produces), we tend to ignore their value until they break down.
The Vicious Cycle
Here is where economics gets sharp. Degradation creates a feedback loop:
- A factory pollutes a river → fish die → fishermen lose income → they move to the city → more pressure on urban resources → more pollution → more degradation.
This is called the tragedy of the commons — when a resource is owned by everyone (a lake, the atmosphere), no single person has an incentive to protect it. Everyone takes, no one maintains.
The Diagram in Words
Picture two curves on a graph. The supply curve of a good (say, plastic bottles) slopes upward. The demand curve slopes downward. The market equilibrium price is where they meet. But there is a third curve above the supply curve — the social cost curve — which includes the damage from pollution. The true cost of those bottles is higher than what the market shows. The gap between the private cost and the social cost is the external cost of degradation. …
Among the many problems facing the environment, two are widely regarded as the most serious because they threaten the entire planet. …
The two most serious environmental issues confronting the world today are global warming and ozone depletion.
Filling the blanks
The global environmental crisis has thrown up several problems, but two stand out as the most pressing threats to the entire planet:
- Global warming — a gradual increase in the average temperature of the Earth's atmosphere and oceans, caused largely by the build-up of greenhouse gases such as carbon dioxide from burning fossil fuels. It leads to melting ice caps, rising sea levels and changing weather patterns. …
- CBSE 2026Set 58/1/11 markMCQQ.The Montreal Protocol was signed in the year 1987 committing nations to __________. (Choose the correct option to fill in the blank) Options : (A) protect biodiversity from any further losses. (B) reduce the impact of global warming. (C) protect ozone layer from depletion incurred due to chlorofluoro carbons. (D) reduce the impact of deforestation.
›Reveal solutionSolution
The Montreal Protocol (1987) was a landmark international treaty specifically targeting ozone layer depletion caused by chlorofluorocarbons (CFCs) and similar substances. Option (C) is correct.
The Montreal Protocol stands as one of the most successful environmental agreements in history, but its purpose is often confused with other global environmental challenges. Understanding what it actually addresses requires distinguishing between different atmospheric problems.
The ozone layer, located in the stratosphere roughly 15–35 km above Earth's surface, absorbs most of the sun's harmful ultraviolet-B radiation. In the 1970s and 1980s, scientists discovered that certain human-made chemicals—particularly chlorofluorocarbons (CFCs) used in refrigerants, aerosol sprays, and foam-blowing agents—were breaking down ozone molecules. When CFCs reach the stratosphere, ultraviolet radiation breaks them apart, releasing chlorine atoms that catalytically destroy ozone in a chain reaction. A single chlorine atom can destroy thousands of ozone molecules before being deactivated.
The discovery of the Antarctic ozone "hole" in 1985 galvanized international action. The Montreal Protocol, signed in 1987 and entering into force in 1989, committed signatory nations to phase out the production and consumption of ozone-depleting substances (ODS). The treaty established binding timetables for developed and developing countries, with provisions for technology transfer and financial assistance through the Multilateral Fund.
Why the other options don't fit:
- Option (A) refers to biodiversity protection, which is primarily addressed by the Convention on Biological Diversity (1992), not the Montreal Protocol. …
- CBSE 2024Set ANNUAL1 markQ.Breathlessness (shortness of breath) is caused by air pollution.
›Reveal solutionSolution
True — air pollution causes respiratory problems such as breathlessness.
Air pollution — caused by smoke, dust, vehicular and industrial emissions — contaminates the air with harmful gases and particulate matter. Breathing polluted air damages the respiratory system and leads to ailments such as breathlessness, asthma, bronchitis and other lung diseases. Hence …
- CBSE 2020Set 58/3/11 markQ.Central Pollution Control Board (CPCB) has identified ___________ categories of large and medium industries as polluting industries. (Choose the correct alternative) (A) 15 (B) 17 (C) 19 (D) 13
›Reveal solutionSolution
The CPCB classifies polluting industries into distinct categories based on their environmental impact; the correct count is 17 categories.
The Central Pollution Control Board (CPCB) is India's apex environmental regulatory body under the Ministry of Environment, Forest and Climate Change. One of its core functions is to monitor and control industrial pollution across the country.
To systematically regulate pollution, the CPCB has developed a classification system that groups large and medium industries based on the type and severity of pollutants they generate. This categorization helps in:
- Setting industry-specific emission and effluent standards
- Prioritizing inspection and monitoring efforts
- Designing targeted pollution control measures
- Allocating resources for environmental enforcement
The classification covers industries ranging from heavy manufacturing (like iron and steel, cement) to chemical processing (fertilizers, pesticides, dyes), thermal power plants, refineries, and others that have significant environmental footprints.
The official classification: …
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